Prediction of System-Level Gear Rattle Using Multibody and Vibro-Acoustic Techniques 2004-32-0063

The objective of this paper is to present the development and the use of a numerical model to predict noise radiated from manual gearboxes due to gear rattle using Computer-Aided Engineering (CAE) technologies. This CAE process, as outlined in this paper, includes measured data, computational flexible multibody dynamics, and vibro-acoustic analysis. The measured data is used to identify and reproduce the input excitation which is primarily generated from engine combustion forces. The dynamic interaction of the gearbox components, including flywheel, input/output shafts, contacting gear-pairs, bearings, and flexible housing is modeled using flexible multibody techniques. The acoustic response to the vibration of the gearbox housing is then predicted using vibro-acoustic techniques. These different technologies are augmented together to produce a virtual gearbox that can be used in noise, vibration, and harshness (NVH) performance evaluations. The developed CAE model has a potential of different benefits of using it in the analysis and performance improvements of gearboxes. One major advantage of using such a CAE model is its promising capability in reducing physical prototypes by virtually testing different design modifications. Such reduction in physical prototypes will lead to a substantial reduction in cost and time.